After restarting Grub doesn’t allow me to choose other than the 1st (Ubuntu 20.04) choice. The cursor won’t move and I have a Windows 10 install I’d like to boot into sometimes. This is all my fault for trying to repair an old Win 7 install, which I was able to do, then upgrade to 10. I’ve been using Boot Repair, Grub Customizer and the other usual suspects but I’m still stuck at the first OS. I can boot into linux, just cannot move the cursor down to launch Windows instead.
Any thoughts? It’s an old Dell and I installed Ubuntu when I ran into a problem with the pre-installed Windows 7. I’ve been happy with Ubuntu and have used it about 3 years. That’s what I deserve for trying to get back into Windows! The reason for which is my purchase of a SDR; there are a number of Win only apps I’d like to try.
Many thanks!
Hey. This could be that Windows 10 is installed in UEFI mode and Ubuntu isn’t. Or something along those lines.
Try changing your boot settings from BIOS to UEFI Only and or make sure both are installed in UEFI mode. Toggle also the secure boot option in BIOS.
Also see: UEFI - Community Help Wiki
It could be related, not sure.
I have heard of similar issues and this might not be an option for you (or the desired suggestion) but upgrading to Windows 11 could fix the issue. I keep reading that dual booting with WIndows 11 is easier/better for a lot of laptops and PC builds.
I think the difference in the two modes was my original problem. I ended up with 5 partitions after upgrading Windows, then not being able to find Grub, and my fumbling after that.
Changing to UEFI left me only an option to boot via USB.
I was able to boot into Windows but the upgrade tool said my cpu wasn’t up to snuff for 11. I did find a NUC for about $360 that comes with a Windows 11 install with a 16GB/512SSD so I may save for that and use the old Dell as my current driver.
But then, a Raspberry Pi may come first, if they become available and more affordable!
Ok cool. Some progress. You may need to reinstall Ubuntu after switching UEFI.
I find Windows 11 UI kinda looks like Gnome. Especially with the floating dash/bar at the bottom and the rounded edges and look of buttons ha.
I was going to say similar. Reinstall Windows 10 with your win7 key, and then a fresh copy of Ubuntu.
Otherwise,
You can try to play with the grub / EFI bootloader from Ubuntu if you’d like, and probably make windows the 1st pick, but that’s alot of hassle, IMO, and I don’t think it will work. 
Ubuntu Manpage: efibootmgr — manipulate the EFI Boot Manager.